Apparatus for hinging a discharge door to an air conditioning unit

ABSTRACT

Apparatus for hinging a discharge door to an air conditioning unit to control the flow of conditioned air from the discharge port of the unit, comprises a pair of coaxially disposed hinge pins, the hinge pins having cylindrical body portions which are frictionally engaged by the door and noncylindrical end portions which are mounted for limited rotation in the housing. The discharge door rotates with the hinge pins to the limited extent the hinge pins are rotatable in the housing, and the door rotates about the hinge pins when the hinge pins are blocked against further rotation. The discharge door opens to the limited extent from its closed position in response to the discharge of air from the discharge port, and is thereafter manually adjustable to control the opening of the discharge port.

United States Patent 11 1 Kincaid et a1.

[4 1 Feb. 5, 1974 APPARATUS FOR HINGBYG A DISCHARGE DOOR TO AN AIR CONDITIONING UNIT [73] Assignee: Carrier Corporation, Syracuse, NY.

[22] Filed: Mar. 5, 1973 [21] Appl. No.: 338,126

3,733,843 5/1973 MacLeod 62/262 Primary Examiner-William J. Wye Attorney, Agent, or FirmD. Peter l-lochberg [5 7] ABSTRACT Apparatus for hinging a discharge door to an air conditioning unit to control the flow of conditioned air from the discharge port of the unit, comprises a pair of coaxially disposed hinge pins, the hinge pins having cylindrical body portions which are frictionally engaged by the door and noncylindrical end portions which are mounted for limited rotation in the housing. The discharge door rotates with the hinge pins to the limited extent the hinge pins are rotatable in the housing, and the door rotates about the hinge pins when the hinge pins are blocked against further rotation. The discharge door opens to the limited extent from its closed position in response to the discharge of air from the discharge port, and is thereafter manually adjustable to control the opening of the discharge port.

6 Claims, 5 Drawing Figures APPARATUS FOR HINGING A DISCHARGE DOOR TO AN AIR CONDITIONING UNIT BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to air conditioning units, and to the means for controlling the discharge of conditioned air from the discharge port of the unit. More particularly, the invention relates to means for preventing the inadvertent closing of the discharge door when the unit is running, to avoid the formation of ice on the evaporator coils of the unit and the subsequent damage which could occur. The invention further relates to means for enabling the manual adjustment of the discharge door of an air conditioning unit.

2. Description of the Prior Art Residential air conditioning units, especially those which extend through the wall of a residence or are mounted in a window of a residence, include a discharge port for discharging conditioned air from the unit into the space to be conditioned, and a door for controlling the opening of the port. When such a unit is not in use, the discharge door is normally closed for the purposes of appearance, to prevent persons from accidentally striking the door, and to prevent the insertion of articles into the discharge port. It is very important that the discharge door be open whenever the unit is operating, because failure to open the door can result in the build-up of ice on the evaporator coils of the unit which could seriously damage the unit. Moreover, such failure to open the door can cause the thermostatic controls of the unit to shut the unit down before the space has been conditioned. It is customary to rely on.

the individual using the unit to be sure that the discharge door is open when the unit is running; however, the user might forget to open the door after the unit has been actuated, or the door could inadvertently be closed while the unit is in use.

An air conditioning unit having a discharge door which is adapted to open in response to the presence of fan pressure from the unit so as to assure that the discharge door will be open whenever the unit is operating, is disclosed in commonly assigned US. Pat. No. 3,421,748 which was issued on Mar. 11, 1969, in the name of Theodore S. Bolton under the title Door Mounting for a Room Air Conditioner Discharge Opening."

SUMMARY OF THE INVENTION An object of the present invention is to prevent the closing of the discharge port of an air conditioning unit when the unit is in operation.

Another object of the invention is to provide a discharge door for the discharge port of an air conditioning unit which opens whenever the unit is discharging air, and which is manually adjustable to control the excharge door hinged on the housing of the unit to open and close the discharge port. The door is secured to the housing by means of a pair of hinge pins having cylindrical body portions which are frictionally engaged by the door, and noncylindrical end portions which are received by openings in the housing, the openings being configured to permit the limited rotation of the pins. The door frictionally engages the hinge pins with a relatively greater force than is required to rotate the hinge pins in the openings of the housing. The hinge pins, with the door attached thereto, are rotatable through a limited angle until the noncylindrical portions are blocked against further rotation by the edges of the openings in the housing. After the noncylindrical portions are blocked against further rotation, the door is rotatable about the hinge pins on the cylindrical body portions. The door and the hinge pins are rotatable through the limited angle from the position in which the door closes the discharge port in response to the exertion of pressure by air being discharged from the port. Thus, it is impossible to operate the unit with the discharge door closed. Once the door has moved through the foregoing limited angle, it is manually adjustable through a large angle by virture of the rotation of the door about the hinge pins.

BRIEF DESCRIPTIONOF THE DRAWINGS FIG. I is a perspective view of a self-contained residential air conditioning unit of the type which extends through an exterior wall of a residence for conditioning the air within the residence, the unit including a discharge door hinged to the housing of the unit according to the invention.

FIG. 2 is a fragmentary, pictorial view of the means by which the discharge door in FIG. 1 is hinged on the unit.

FIGS. 3 and 4 are partial top and rear plan views, respectively, of the hinging apparatus for mounting the discharge door on the unit shown in FIG. 1, with a portion of FIG. 4 being cut away to show interior components of the apparatus.

FIG. 5 is a partial side view of the unit shown in FIG. I, with a portion being cut away to indicate an end view of the hinging apparatus used for securing the discharge door to the unit.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention provides an extremely simple yet efficient apparatus for closing the discharge port of an air conditioning unit when the unit is not in operation, while assuring that the discharge port will be open whenever the unit is operating and is discharging air through the discharge port. The preferred embodiment contemplates a discharge port extending substantially across the face of an air conditioning unit, and a discharge door hinged near an edge of the port for opening and closing the port. The door is advantageously attached to the cylindrical body portions of a pair of coaxial hinge pins such that the door is rotatable with the pins until the rotation of the pins is blocked, whereafter the door is rotatable relative to the pins. The pins have noncylindrical end portions which extend outwardly from the sides of the door and are received by noncircular openings in the housing of the unit. The latter openings are configured such that the hinge pins are rotatable through a limited angle, after which they abut against the edges of the openings to block the subsequent rotation of the pins. The pins with the door mounted thereon are easily rotatable through the foregoing limited angle, so that the pressure exerted by air flowing through the discharge port is sufficient to open the door to assure that the door will always be open whenever the unit is operating, whereby ice build-up on the evaporator coils and premature shutting down of the unit by thermostatic controls in the unit are prevented. Once the discharge door is opened, it is continuously adjustable throughout the range through which it can be opened, by virture of the frictional engagement of the pins by the door.

Referring now to the drawings, FIG. 1 shows an air conditioning unit 2 which is of the type used frequently for installation in an exterior wall of a residence for conditioning the air within the residence. The unit is self-contained in that it contains within its housing the complete refrigeration circuit and associated components necessary to render the unit fully functional. Air conditioning unit 2 includes a housing 4 including a top wall 6, opposed side walls 8, and bottom and back walls (not shown). Appropriate vents (not shown) are provided in selected walls of housing 4 for directing ambient air across the condenser coil of the circuit for removing heat transferred from refrigerant condensing within the coil. The front of the unit, which is normally the only portion of the unit visible from the interior of the residence being served thereby, includes a removable front panel 10, a discharge port 12, and a control panel 14 having operating buttons 15. Conditioned air which has been cooled during its passage over evaporator coils within the unit is forced by a fan through discharge port 12 into the space being conditioned. A protective and decorative grille 16 can be provided across discharge port 12, the grille design being such as not to restrict the flow of air through the port. Access to the interior of the unit is had by removing front panel which is held in place by appropriate tracks in the housing and by a base piece 18 of the housing. A discharge door 20 is hinged at the lower edge of discharge port 12, and is pivotable about the hinge pins on which it is mounted to open and close discharge port 12.

Door 20 is mounted so that it will open from its closed position by an amount sufficient to discharge enough air from discharge port 12 to prevent the formation of ice on the evaporator coils in response to the discharge of air from the unit. The door is manually adjustable to a variety of positions beyond the aforementioned limited opening of the door to control the flow of air from discharge port 12. Referring to FIGS. 2 through 5, the means by which door 20 is hinged to the unit is shown. The drawings show one of a pair of identical hinge pins 22 which are frictionally engaged by door 20 at the lower edge thereof, the hinge pins being in axial alignment and having portions extending beyond the sides of the door. Each hinge pin comprises a cylindrical body portion 24 about which is wrapped the lower edge or gripping portion 26 of discharge door 20. It is contemplated that discharge door 20 be fabricated from some resilient material such as sheet metal, and that prior to the assembly of the hinge pins with the door, the outer diameter of cylindrical portion 24 of each of the hinge pins be somewhat larger than the inner diameter of the tubular lower edge portion 26 of the door. By virtue of this dimensional relationship, pins 22 are maintained in firm frictional engagement with door 20. Each of hinge pins 22 is provided with one noncylindrical end portion 28. In the embodiment depicted in the drawings, end portion 28 has an oblong cross section. When hinge pins 22 are assembled within section 26 of discharge door 20, end portions 28 extend from the opposite outer ends of the section.

Housing 4 of air conditioning unit 2 is adapted to receive the end portions 28 of hinge pins 22 to pivotally mount door 20 on the unit. Accordingly, each of side walls 8 includes an extension which is wrapped around the front side edges of the unit, the edges being adapted to receive end portions 28. Each extension includes a first fold 30 which is perpendicular to sides 8 and is inwardly disposed therefrom. A second fold 32 extends normal to fold 30, parallel to side wall 8 and towards the interior of unit 2. A third fold 34 is perpendicular to fold 32 and extends away from side wall 8. A pair of openings 36 are disposed in an opposing relationship in each of folds 32 of housing 4. These openings are provided for receiving hinge pins 22 mounted in the lower portion of discharge door 20, and are located so that the door can completely close discharge opening 12. Each opening 36 has a configuration similar to the cross section of end portion 28, but is dimensioned larger than that cross section so that it can freely accommodate that portion of the hinge pins. The dimensional relationships of end portion 28 and opening 36 are such that the hinge pin can rotate through a limited angle within the opening before it abuts against the edge of opening 36, whereby further rotation of the hinge pin in the same direction is blocked. By virtue of the loose fit of end portion 28 in opening 36, rotation of the hinge pin through the previously mentioned limited angle requires very little force.

When the hinge pins are assembled in discharge door 20 and in fold 32 of housing 4, the operation of the discharge door is very simple. Assuming an operator has displaced an appropriate one of control buttons 15 to actuate air conditioning unit 2, conditioned air is discharged through discharge port 12. If during the operation of the unit door 20 should inadvertently be closed, or if the control mechanism for the unit were disposed such that the unit could be actuated while door 20 were closed, the pressure of discharge air passing through discharge port 12 would exert a force on discharge door 20. This force, and the resultant torque, would effect the rotation of door 20 outwardly from the unit about the axis A-A of the coaxial hinge pins. Door 20 opens in this manner until end portion 28 abuts against the edges of openings 36 so as to block further rotation of the hinge pins. Door 20 can be rotated to open the discharge port further by merely grasping the door and turning it outwardly from the unit. Since the cylindrical portions'24 of the hinge pins are in frictional engagement with the tubular portion 26 of door 20, the door is rotatable about the hinge pins when such manual force is exerted thereon. The extent to which discharge door 20 can be opened depends upon the design of the door and adjacent portions of housing 4 and front panel 10. In most instances, door 20 would advantageously be openable through an angle somewhat in excess of so that full flow through discharge port 12 would be possible, and so that air from the unit could be directed downwardly when the unit was mounted above persons in the space being conditioned.

Fabrication of the foregoing apparatus is very simple. Housing 4 and discharge door 20 are conventionally made from sheet metal, so that folds 30, 32 and 34, as well as the tubular portion 26 of door 20 can be made with conventional dies. Openings 36 would normally be made using conventional stamping procedures. Alternatively, suitable plastics such as thermoplastic stock could be formed into the desired configuration using known methods. The door-hinge pin assembly can easily be installed in housing 4 by merely urging side walls 8 outwardly, aligning the end portions 28 of the hinge pins 22 with the openings 36, and releasing the side walls. Tubular portion 26 preferably is curled inwardly from the front of the unit for aesthetic purposes.

The nature of folds 30, 32 and 34 renders them useful for functions in addition to the mounting of door 20. As indicated earlier, front panel is removably mounted between side walls 8, and the tracks for receiving the side portions of front panel 10 can at least partially be formed from fold 34. Moreover, fold 34 can serve as a front stop for discharge door so that the door will not slam against control panel 14, control buttons 15, or grille 16. When fold 34 is so employed, one or more resilient pads or strips 35 can be affixed to the fold or to door 20 to cushion the closing of the door and to improve the sealing engagement of the door when it is closed. The preceding construction does not at all detract from the appearance of the unit since the entire hinge assembly is hidden from exterior view, and since the door 20 can be designed in harmony with the rest of the unit.

From the preceding description it is clear that the objects of the invention have been fully achieved by the preferred embodiment of the invention. The automatic opening of discharge door 20 assures the prevention of ice build up on the evaporator coils of the unit and further assures that the unit will not be prematurely shut down by the thermostatic controls. The discharge door of the air conditioning unit is manually adjustable through a wide range of angles, and the door can be closed without fear that it would be left closed while the unit is running. The invention is very economical to manufacture and simple yet efficient in operation.

The invention has been described in detail with particular reference to a preferred embodiment thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

We claim:

1. In an air conditioning unit having a housing and a discharge port in the housing for discharging air from the unit, apparatus for opening and closing the dis- 6 charge port, said apparatus comprising:

a discharge door dimensioned to cover the discharge hinge pin means for connecting said discharge door to the housing for rotation between port opening and port closing positions, said hinge pin means including a first portion having a generally circular cross section and a second portion having a noncircular cross section;

gripping means associated with either said door or the housing for frictionally engaging the first portion of said hinge pin means to allow the forced rotation of said hinge pin means relative to said gripping means; and

receiving means associated with the other of said door and housing with which said gripping means is associated for receiving the second portion of said hinge pin means, said receiving means being dimensioned to permit the free rotation of said hinge pin means through a limited angle and to block said hinge pin means against rotation beyond said limited angle;

whereby said door is freely rotatable through the limited angle from the port closing position in response to the discharge of air from said port, and said door is further rotatable in response to the further application of force on said door.

2. Apparatus according to claim 1 wherein said gripping means extends along an edge of said door, and the second portion of said hinge pin means comprises a pair of noncylindrical elements extending out of opposite ends of said gripping means, and said receiving means comprises a pair of openings in the housing on opposite sides of the discharge port for receiving said non-cylindrical portions.

3. Apparatus according to claim 2 wherein said hinge pin means comprises a pair of hinge pins, the first portion of each of said hinge pins being engaged by said gripping means.

4. Apparatus according to claim 1 wherein the discharge port and said door have rectangular configurations having upper and lower edges, and said gripping means extends along the lower edge of said door.

5. Apparatus according to claim 1 wherein said gripping means comprises an edge of said door wrapped around the first portion of said hinge pin means.

6. Apparatus according to claim 1 wherein the second portion of said hinge pin means has an oblong cross section. 

1. In an air conditioning unit having a housing and a discharge port in the housing for discharging air from the unit, apparatus for opening and closing the discharge port, said apparatus comprising: a discharge door dimensioned to cover the discharge port; hinge pin means for connecting said discharge door to the housing for rotation between port opening and port closing positions, said hinge pin means including a first portion having a generally circular cross section and a second portion having a noncircular cross section; gripping means associated with either said door or the housing for frictionally engaging the first portion of said hinge pin means to allow the forced rotation of said hinge pin means relative to said gripping means; and receiving means associated with the other of said door and housing with which said gripping means is associated for receiving the second portion of said hinge pin means, said receiving means being dimensioned to permit the free rotation of said hinge pin means through a limited angle and to block said hinge pin means against rotation beyond said limited angle; whereby said door is freely rotatable through the limited angle from the port closing position in response to the discharge of air from said port, and said door is further rotatable in response to the further application of force on said door.
 2. Apparatus according to claim 1 wherein said gripping means extends along an edge of said door, and the second portion of said hinge pin means comprises a pair of noncylindrical elements extending out of opposite ends of said gripping means, and said receiving means comprises a pair of openings in the housing on opposite sides of the discharge port for receiving said non-cylindrical portions.
 3. Apparatus according to claim 2 wherein said hinge pin means comprises a pair of hinge pins, the first portion of each of said hinge pins being engaged by said gripping means.
 4. Apparatus according to claim 1 wherein the discharge port and said door have rectangular configurations having upper and lower edges, and said gripping means extends along the lower edge of said door.
 5. Apparatus according to claim 1 wherein said gripping means comprises an edge of said door wrapped around the first portion of said hinge pin means.
 6. Apparatus according to claim 1 wherein the sEcond portion of said hinge pin means has an oblong cross section. 